MIP1501
ASSIGNMENT 2 2025
UNIQUE NO. 178117
DUE DATE: 3 JULY 2025
, Question 1 (36)
1.1.1 Problem-Solving Level
Problem:
John had a few marbles. He doubled them and then received three more from Thabo.
Now he has 21 marbles. How many did he have before?
Solution using the bar model:
Let’s say John originally had x marbles.
He played and doubled his marbles: now he has 2x.
Then Thabo gave him 3 more: 2x + 3
Now he has 21:
→ 2x + 3 = 21
Step-by-step solution:
1. Subtract 3 from both sides:
2x + 3 - 3 = 21 - 3
→ 2x = 18
2. Divide both sides by 2:
2x ÷ 2 = 18 ÷ 2
→x=9
Answer: John had 9 marbles before.
How to explain this to learners:
Use pictures or blocks. Show a bar for the original marbles, double it, then add 3 blocks.
Ask: how can we find the original number that, when doubled and added to 3, gives 21?
ASSIGNMENT 2 2025
UNIQUE NO. 178117
DUE DATE: 3 JULY 2025
, Question 1 (36)
1.1.1 Problem-Solving Level
Problem:
John had a few marbles. He doubled them and then received three more from Thabo.
Now he has 21 marbles. How many did he have before?
Solution using the bar model:
Let’s say John originally had x marbles.
He played and doubled his marbles: now he has 2x.
Then Thabo gave him 3 more: 2x + 3
Now he has 21:
→ 2x + 3 = 21
Step-by-step solution:
1. Subtract 3 from both sides:
2x + 3 - 3 = 21 - 3
→ 2x = 18
2. Divide both sides by 2:
2x ÷ 2 = 18 ÷ 2
→x=9
Answer: John had 9 marbles before.
How to explain this to learners:
Use pictures or blocks. Show a bar for the original marbles, double it, then add 3 blocks.
Ask: how can we find the original number that, when doubled and added to 3, gives 21?
